Add the dependent repo and article for breaking changes in the razor compiler

[BillWagner]

Update the docfx.json and TOC to include the two razor compiler breaking changes articles:

• Since .NET 8 GA
• Since .NET 9 GA

The titles also need a bit of language changes as well

[BillWagner]

@tdykstra I added this to the dotnet/docs sprint project just because I look there more often. Go ahead and add it to the ASP.NET docs project if you want.